Abstract #1599

Neurophysiological Underpinnings of Ketamine-Induced Negative BOLD Response.

Naranjargal Dashdorj¹, Mirjam I. Schubert¹, Malcolm Prior², Rob Mason³, Dorothee Auer¹

¹Academic Radiology, University of Nottingham, Nottingham, UK; ²Brain and Body Centre, University of Nottingham, Nottingham, UK; ³School of Biomedical Sciences, University of Nottingham, Nottingham, UK

In depth understanding of drug-induced BOLD response and its underlying neural activity is essential for correct interpretation of phMRI. In this study we characterized ketamine induced BOLD signal changes in the hippocampus in a parallel electrophysiology and phMRI setup in rodent brain. Ketamine 25mg/kg i.p administration evoked both neural activity decrease (multi-unit activity and local field potential) and negative BOLD response (NBR) that was moderately correlated. To the best of our knowledge this is the first study to investigate drug-induced negative BOLD changes and its underlying neuronal activity changes. Our results suggest that drug-induced BNR reflects reduced neural activity.